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Special offensive plays

“Spiking” the football
Because an incomplete pass stops the game clock, a team’s quarterback will sometimes “spike” the ball (throw it directly at the ground) in order to stop the clock without using a time out. This is most commonly done when a team is trying to score points late in the second or fourth quarter and/or when the team has run out of time-outs.

Downing a knee
This play is essentially the opposite of spiking the ball. Because the game clock does not stop after a player is tackled in bounds (except after a change of possession or an injury) a team’s quarterback will sometimes kneel immediately after the ball is snapped to him in order to use up time on the clock. By using up time at the end of the game in this manner, a team can deny its opponent the opportunity to score, or can hasten the end of the half (halftime) or the end of the game when the score is tied, sending the game into overtime.